Periodically log transfer progress for RDE SFTP uploads

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=201172975

java/google/registry/rde/LoggingSftpProgressMonitor.java

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+// Copyright 2018 The Nomulus Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package google.registry.rde;
+
+import com.google.common.collect.ImmutableMap;
+import com.google.common.flogger.FluentLogger;
+import com.jcraft.jsch.ChannelSftp;
+import com.jcraft.jsch.SftpProgressMonitor;
+import google.registry.util.Clock;
+import javax.inject.Inject;
+import org.joda.time.DateTime;
+import org.joda.time.Duration;
+
+/** A progress monitor for SFTP operations that writes status to logs periodically. */
+public class LoggingSftpProgressMonitor implements SftpProgressMonitor {
+
+  private static final FluentLogger logger = FluentLogger.forEnclosingClass();
+  private static final long LOGGING_CHUNK_SIZE_BYTES = 5 * 1024 * 1024;
+
+  private final Clock clock;
+  private long bytesOfLastLog = 0;
+  private int callsSinceLastLog = 0;
+  private DateTime timeOfLastLog;
+
+  @Inject
+  LoggingSftpProgressMonitor(Clock clock) {
+    this.clock = clock;
+  }
+
+  /** Nice display values for SFTP operation modes. */
+  private static final ImmutableMap<Integer, String> OPERATION_MODES =
+      new ImmutableMap.Builder<Integer, String>()
+          .put(ChannelSftp.OVERWRITE, "OVERWRITE")
+          .put(ChannelSftp.RESUME, "RESUME")
+          .put(ChannelSftp.APPEND, "APPEND")
+          .build();
+
+  @Override
+  public void init(int op, String src, String dest, long max) {
+    timeOfLastLog = clock.nowUtc();
+    logger.atInfo().log(
+        "Initiating SFTP transfer from '%s' to '%s' using mode %s, max size %,d bytes.",
+        src, dest, OPERATION_MODES.getOrDefault(op, "(unknown)"), max);
+  }
+
+  @Override
+  public boolean count(long count) {
+    callsSinceLastLog++;
+    long bytesSinceLastLog = count - bytesOfLastLog;
+    if (bytesSinceLastLog > LOGGING_CHUNK_SIZE_BYTES) {
+      DateTime now = clock.nowUtc();
+      logger.atInfo().log(
+          "%,d more bytes transmitted in %,d ms; %,d bytes in total. [%,d calls to count()]",
+          bytesSinceLastLog,
+          new Duration(timeOfLastLog, now).getMillis(),
+          count,
+          callsSinceLastLog);
+      bytesOfLastLog = count;
+      callsSinceLastLog = 0;
+      timeOfLastLog = now;
+    }
+    // True means that the upload continues.
+    return true;
+  }
+
+  @Override
+  public void end() {
+    logger.atInfo().log("SFTP operation finished.");
+  }
+}